Mesh mod discussion -- tag along

[RokleM]

For those of you that haven't tried the mesh mod and are wonder how it works, looks like it's time to ride along

My GEO is a year and half old with dual Gen-X 4100's. They've run non-stop the entire time, so have taken quite a beating. They still do a pretty good job, but I'm looking to make them preform like they did new, or better if possible. My main chamber is 8x24.

I already purchased the flow meter. The 4100 I have felt is kind of "weak" recently is only registering 2-2.5 LPM. The "stronger" one is pulling 4-5.5 LPM (jumps up and down). They claim to be able to easily get 15-19 LPM out of the pumps. I don't think I'll want to go this high with both as I'll probably blow the lid right off the top of the skimmer.

My plan as it stands now:
1) I have a spare 4100, and I'm going to try swapping out the impeller before I mod the weaker of the two to confirm or deny it's the impeller that has issues.

2) I need to acquire some mesh. If anyone has some of the P4 or P5 mesh (P4 preferred), please let me know. If not, it's $30ish for 40" by 96", which is more than I'll use if I decide to mod 50 pumps (so obviously I'll have some extras if anyone else wants to try it).

3) I'll likely mod the weaker of the two pumps first to see how much the performance of the pump changes. From there I'll see how drastically it impacts my skimmer performance.

4) Decide if one pump was enough or if two is necessary. It's even possible that if one pump is doing so well, I could cap off and remove the second pump entirely.

[Treg]

2.5 LPM?

That seems pretty low.

Have you tried to just clean the pumps real well?
Soak it in easy clean over night and clean out that air nipple with a drill bit.

That would probably help a lot too. Then Mod.

[Andrew]

Are you using the stock Gen-x venturis? I would make a new one and make the air intake larger. This will help with more air flow as well as doing a mesh mod.

[RokleM]

Originally posted by Treg
2.5 LPM?

That seems pretty low.

Have you tried to just clean the pumps real well?
Soak it in easy clean over night and clean out that air nipple with a drill bit.

That would probably help a lot too. Then Mod.

They were cleaned intensely a few months ago, but yes I plan on tearing it down and testing again before modifications start.

Originally posted by Andrew
Are you using the stock Gen-x venturis? I would make a new one and make the air intake larger. This will help with more air flow as well as doing a mesh mod.

Nope, GEO's setup.

[RokleM]

Quick tear down of both pump showed the slow pump in "ok" condition. The pieces didn't seem fixed on the shaft as they are on my other two pumps (didn't try to loosen them too much). However after a cleaning it's running just as well as my "good" pump. Also found my 4100 backup has the magnet busted and corroded. It hasn't been used since I cycled my live rock in my 180.

SO... Both pumps are operating almost identically with an average of about 5 LPM.

Now to find some mesh

[TacoKing]

Let me know if you find some. I want to mod my Sedra 9000.

[Bcollins111900]

Eric, ebay has it really cheap.

[RokleM]

Originally posted by Bcollins111900
Eric, ebay has it really cheap.

Yup, I picked up a small piece. Shipped from Ohio too, so which one of you are selling?

Obviously, if anyone wants to borrow my flowmeter to do testing, that's fine by me.

[zzak]

Damn just saw this, I have mesh if you need more, like two 4"x5" pieces.

[RokleM]

No updates as of yet. The ebay seller decided to go on vacation after posting items, so it's just now shipping.

[Ithreeputt2]

Take pictures if you can I would love to see it in action.

Steve

[RokleM]

Originally posted by RokleM
However after a cleaning it's running just as well as my "good" pump.

SO... Both pumps are operating almost identically with an average of about 5 LPM.

First off, in less than 12 hours, this pump went back to the weak stance. However, now modded, it seems to be doing better. I'll see if it stays at this rate long term.

Note (discussed below), the stock wattage on a GenX 4100 is 70w.

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So, I started my modding. First off, stock GenX 4100 needle wheel impeller. These were running at 50w when the air holes are plugged, 45w when pulling air.



There are thousands of posts about the mesh mod with hundreds of different techniques and materials. The first one I tried is two layers, three zip ties, and a loose zip tie.







This resulted in about 7 LPM. This is about a 50% increase (pretty much like strapping on a 3rd 4100), but far shy of the 15-19 people claim to get. The pumps dropped to 45w running without air, and 40w when pulling air. That's a 5w drop after the mod.

FYI as well, I've seen posts stating that the 4100 runs fine without the shaft. I decided to try this, and can confirm that it runs fine without it, but there was no change in performance as a result.

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I then tried another style, which is 3 layers, tightly clamped, and making sure to remove all of the material from near the shaft.



This worked a bit better. It was pulling 11.5 LPM, over double my original numbers. As well, the watts dropped to 33, 12 less than the original.

At this point, I'm decently content to leave it be. If I was building a new skimmer and wanted to put "weaker" pumps on it than required due to maximizing the mesh mod's advantages, then I would likely pursue it further. As it is, I've had to drop the water levels a few inches to compensate for the additional air bubbles.

I do however feel I know why I'm not hitting 15-19 LPM. Most have setup their air so that as the tube enters the pipe in front of the pump, it blocks a decent amount of the flow. As well, they cut it at approximately a 45-60 degree angle, with the opening towards the pump. This forces the pump to pull more air due to the angle and blocking of flow. If you look at some of the threads, you'll see what I mean. Mine has the tube into a thread that basically puts it even or slightly inserted into the pipe. I'm not at the point I feel the need to start drilling holes in my GEO to get that much air into the system.

So... thoughts at this point are works for me

[Andrew]

Nice When my DAS skimmer arrives I'm going to mod the impellers which a mesh wheel to see how much it improves the skimmer.

[Steven Pro]

The only concern I have with these modifications is it would seem very likely that the impellor is now unbalanced. I would think this would eventually put some uneven wear on the shaft, impellor magnet, or motor housing due to the impellor wobbling. What are your thoughts on this?

[RokleM]

Originally posted by Steven Pro
The only concern I have with these modifications is it would seem very likely that the impellor is now unbalanced. I would think this would eventually put some uneven wear on the shaft, impellor magnet, or motor housing due to the impellor wobbling. What are your thoughts on this?

I completely agree Steven that it could be an issue in the future. However, I have not yet read any posts where this has surfaced (granted many have only had it modified for 3-6 months). When the mesh was loose, it seemed as though he pumps were slightly louder. This could be a sign of potential imbalance. However, when I tightened it down as listed in the last picture, they appear to be the same volume and vibration as the unmodified version. I don't sense any extra vibration.

So the truth is, only time will tell I plan to break the pumps down in a week, two weeks, a month, 3 months, etc to see if I can find any potential problems. That would include excessive wear, binding, loose or displaced mesh, etc.

[ataylo13]

Tagging along to see long term effects. Keep up the good work RokleM.

[jakano]

my sedra 5000 has been meshmodded for several months now and i have yet to see any ill effects from it. this thing still skims like a beast, way more than it did before i did the mod.

[Big Boy69]

Did anyone ever do this on a mag 9.5 or stock berlin pump?

[MarineFishGuy]

I am using a Mag 7 to run my Berlin 250.
I have thought about giving this a try, but I would want to buy a new Impeller first, just in case.
Especially if it can cut down on electricity consumption.
Would I need to replace the stock Venturi on my Berlin 250 to make this work as expected.
My only other concern is too many bubbles. If I blow into the tube, I can force enough bubbles into the reaction chamber to cause it to flow swiftly into the collection cup.
Would I need to consider a Neck extension to avoid a watered down skimmate or collection cup overflow?
Right now I pull about a half collection cup every 2-3 days.
Thanks for any tips.
Ken

[Big Boy69]

I was also wondering iof I would have to remove the venturi from my Berlin to make this work.
My pump is in the sump and I have about 2' of tube going to the skimmer.

[RokleM]

So far, the performance remains constant. I have to take it apart again this weekend, but I've seen no signs of extra wear or anything coming loose.

As for the other pumps and skimmers, I would suggest hitting the DIY forums and looking at the long mesh mod threads (multiple thousands of posts). I was testing with the 4100 and GEO specifically. I know a lot of people have posted on a large number of pumps and skimmers, so that is likely your best resource to see if you can find someone that has your same equipment. Some setups have yielded great results, for some the design of the skimmer or results caused them to abandon the mesh mod or make major modifications to their skimmers (I saw one of a guy who had to add something like a 2' neck to his small skimmer due to the increased air and the design).

[szwab]

I believe I am going to have to give this a try. After reading all the positives it seems like it's worth a try. Thanks for posting up all the good info Eric!

[jakano]

It really does make a huge difference in the performance of a skimmer.

[Big Boy69]

I went to Lowe's last night and couldn't find any of the mesh stuff.
I checked where they have all the grill stuff, the cleaning supplies area and the tool section.

Where do you find it????????????????????

[RokleM]

Originally posted by Big Boy69
I went to Lowe's last night and couldn't find any of the mesh stuff.
I checked where they have all the grill stuff, the cleaning supplies area and the tool section.

Where do you find it????????????????????

Originally posted by Bcollins111900
Eric, ebay has it really cheap.

Originally posted by RokleM
Yup, I picked up a small piece. Shipped from Ohio too, so which one of you are selling?

Obviously, if anyone wants to borrow my flowmeter to do testing, that's fine by me.